Dishwashers have become an integral part of everyday household use. Typical dishwashers use water pumped into a tub to clean dishes and utensils. In a typical cycle there are multiple water fills with intermediate pump outs. If a malfunction occurs that results in excessive water input or failure to pump out, flooding may occur. Many dishwashers, either with a stainless steel or a plastic tub, depend solely upon the function of a mechanical float for physically activating a float switch, in response to a flood condition within the tub. In general, the stem of the float extends downwardly from the float through a central opening in the switch support housing and outwardly of the tub in order to activate the float switch. As such, since the stem of the float must move freely through the central opening, the central opening may be configured to be open to atmosphere inside the tub. This open-to-atmosphere condition may thus create a potential path for water to leak out of the unit.
A flood condition in the dishwasher could occur due to a single component failure or a combination of component failures. For example, a sticking or otherwise defective float switch may fail to properly signify a high water level condition and thereby cause a flood condition. Often times, the float switch may be the sole provision for detecting the high water level condition. In some instances, combinations of a faulty water inlet valve, a clogged drain filter and/or drain hose, and/or a faulty float switch can also cause a flood condition.
Thus, there is a need for an effective method and system for preventing overfilling in a dishwasher, as well as a need to diagnose potential malfunctions in particular components of the dishwasher causing the overfilling.